System and Method to Detect the Presence of a Child in a Car Seat

ABSTRACT

A system ( 1000 ) and method that detects a presence of at least one object ( 401 ) comprises a pad ( 100 ) and a receiver ( 200 ). The pad ( 100 ) comprises a communication element ( 102 ), a unique identifier, a power source ( 101 ), a switch ( 103 ) configured to adapt a power state from “off” to “on” by means of at least one object ( 401 ) closing the switch ( 103 ) disposed between the power source ( 101 ) and the communication element ( 102 ). The receiver ( 200 ) comprises an analysis element ( 203 ) storing the unique identifier of at least one pad ( 100 ) and a communication element ( 204 ) in communication with at least one pad ( 100 ) when the pad ( 100 ) is powered on. The receiver ( 200 ) determines a presence state of at least one object ( 401 ) when the receiver ( 200 ) is in communication ( 300 ) with the powered pad ( 100 ). The receiver ( 200 ) determines the presence state when the receiver ( 200 ) loses communication ( 300 ) with the pad ( 100 ). The receiver ( 200 ) further generates notifications with the determined objects ( 401 ) presence state.

FIELD OF THE INVENTION

The invention relates to a system and method for determining the presence of an object on a pre-determined location through the use of Bluetooth™ Low Energy, universal unique identifier presence, and range information.

BACKGROUND OF THE INVENTION

Every year, children are left in a car by their caregiver, causing injury and in some cases, death. “Mind on a daily task” is a reason for a caregiver unintentionally leaving a child alone in the car. This detrimental problem could be resolved by an invention that assists a caregiver without changing their daily routine while providing peace-of-mind that they will be reminded if they accidentally forget their child in the car. Consumer expectations for interactive, smart devices are growing every year. Devices of the past relied on being serviced and checked by the user. New, smart devices check on something for a user and only tell the user when something is important. With this concept in mind, this system and method will lend itself to children being at a lesser risk of being left behind.

The system and method proposed works as a one-time installed application on a receiver, one-time placement of the presence indicator, a battery conservation method that only uses power when needed to last the life of the child's car seat life phase, and provide customizable notifications to fit the caregiver's needs.

DISCUSSION OF THE RELATED ART

Many solutions that exist today require complex sensors, active intervention by the user, and/or require a system to always be powered. Common technical challenges in current inventions are managing power and the need for specific sensors to determine if an event occurred. Sensors require additional power, cost and in some cases, complicated logic to prevent false alarms. Properly managing power can be the difference of an invention that receives long-term consumer use or one that is disregarded due to constant battery changes/charges. In some inventions, the use of a low power, stand-by mode has been implemented to save on battery life between uses. However, low power still means power usage, especially since children use car seats for more than several years. This device should also conserve battery life as much as possible to maintain viability over the intended car seat life-stage of the child.

Bluetooth™ low energy (Bluetooth™ 4.0) or BTLE, specifically Apple Inc.'s iBeacon, has opened the door to alert systems that require little energy to communicate resulting in years of battery life. Unlike traditional Bluetooth™ protocols, in iBeacon, there is no pairing needed between the receiver and BTLE radio. In this regard, one could passively keep track of multiple BTLE radios within a pre-determined area. The distance of the iBeacon from the receiver can be determined by ranging protocols: immediate (centimeters away), near (several meters), and far (greater than 10 meters). A smart safety device should be able to fit in a consumer daily routine unnoticed until information is needed.

SUMMARY OF THE INVENTION

This invention addresses the disadvantages cited in prior art, in terms of seamlessly fitting into a caregiver's routine improving the use experience, simplification of necessary components, improved power management, and improvements to the user experience. In one aspect, a presence indicator comprises a pad and a receiver. The pad comprises at least one communication element with a universally unique identifier. The pad further comprises a power source and a switching element between the power source and the communication element. The receiver comprises an analysis element storing the unique identifier of at least one pad, a communication element in communication with at least one pad when the pad is powered on. When an object is on the pad, the switching element is closed, powering the pad thus initiating communication between the pad and receiver. The receiver is further able to determine the last known range when communication is lost. No power is used when an object is not present, therefore extending the life of the battery.

In another aspect, a method for determining a presence state of at least one object comprising: a seat containing a pad, a means by which an object closes a power switch disposed between a communication element and a power source powering the pad to broadcast a unique identifier; a receiver containing an analysis element storing the unique identifier of the pad, with the analysis element matching the stored unique identifier of the unique identifier broadcasted by the powered pad; the receiver determining the last known range when communication is lost; a receiver providing a notification associated with an interpreted communication state of the receiver and the pad.

OBJECTS AND ADVANTAGES

Accordingly, several objects and advantages of the system are

-   -   No need for traditional sensors that require power to indicate         the presence of a child. A mechanical switch is closed between         the power source and communication element with the child's         presence on the pad;     -   No sensors reduce complexity, software/memory bandwidth and cost         of design;     -   Battery life is further conserved due to only being used with         the child activates the switch while in the car seat;     -   No need for the caregiver to activate the system each time when         the child is in the seat (the receiver recognizes this via         communication with the pad);     -   The iBeacon protocol allows for several systems if desired due         to the non-pairing nature of iBeacon compared to conventional         Bluetooth™ protocol;     -   Notifications are sent based on scenarios of lost signal and         last distance reading to reduce unnecessary information being         provided to the caregiver;     -   The caregiver can tailor the level of interaction with the         receiver;

Further objects and advantages of the invention will become apparent from a consideration of the drawings and ensuing description.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the drawings and features will be readily apparent through consideration of the drawings.

FIG. 1. shows a schematic of the system;

FIG. 2. shows a schematic of the switch in an open state (power off);

FIG. 3. shows a schematic of the switch in a closed state (power on);

FIG. 4. shows a side view of the pad on a child seat and a child on the pad;

FIG. 5. shows a side view of the pad placement in the seat;

FIG. 6. shows a side view of the pad placement on the headrest of the seat;

FIG. 7. shows a side view of the pad placement in the headrest of the seat;

FIG. 8. is a view of the receiver with a reminder notification message;

FIG. 9. is a view of the receiver with a reminder notification message;

FIG. 10. is a view of the receiver with a reminder notification message;

FIG. 11. is a flow diagram of the system user scenario embodiment (range available);

FIG. 12. is a flow diagram of the system user scenario embodiment (range not available).

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1., a system 1000 comprises a pad 100 and a receiver 200. The pad 100 comprises a power source 101, a communication element 102, a switch 103, and an enclosure 104. The receiver 200 comprises a power source 201, an antenna 202, an analysis element 203, and communication element 204 a display element 205. The receiver 200 and pad 100 communicate via a wireless communication protocol 300.

The Pad

In one aspect the system 1000 comprises a pad 100. The pad 100 contains a power source 101. An exemplary power source is a Panasonic CR 2032 3-volt lithium coin cell battery. However, the power source may be rechargeable or disposable. The pad 100 also contains a communication element 102. An exemplary communication element 102 is the LightBlue™ Bean iBeacon by Punch Through Design, LLC, in San Francisco, Calif. The LightBlue™ contains an LBM313 chip and antenna designed for Bluetooth™ Low Energy communication. However, any communication protocol with unique identifier(s) and ranging abilities may be used. The pad 100 also contains a switch 103 between the power source 101 and the communication element 102. The switch 103 turns the power 101 to the communication element 102 on or off. As shown in FIG. 2, an exemplary switch 103 is a metal cantilever switch 106 and a landing pad 107 that do not make contact in an open circuit configuration in which the communication element 102 receives no power from the power source 101. As shown in FIG. 3, when a load 108 from an object is placed on the cantilever switch 106, it makes contact with the landing pad 107 closing the circuit between the power source 101 and communication element 102.

The following embodiment describes how the switch 103 is made. The CR2032 coin cell holder is removed from the LightBlue™ Bean. Wires replace the previous electrical connections of the coin cell holder. One of the wires includes a switch 103 to act as the presence indicator and conserve battery life when no there is no object presence. The modified LightBlue™ Bean iBeacon, coin cell battery, wires and switching mechanism is housed in an enclosure 104. The exemplary enclosure is molded silicone with a top and bottom that fit together by the top having ridges that overlap the bottom. The enclosure can be made of any material that protects the electronics while allows the presence of an object to close a switch inside the enclosure. The electronics inside are positioned such that the switch is in contact with the enclosure. The diameter of the enclosure is 80 mm in diameter and 10 mm in thickness.

The Receiver

In another aspect, the system 1000 in FIG. 1., comprises a receiver 200, a power source 201, an antenna 202, an analysis element 203, a communication element 204, and a display element 205. Exemplary receivers with iBeacon capabilities are iPhone 4s or later, iPad (3^(rd) generation) or later, iPad mini or later, or iPod touch (5^(th) generation) or later. Future devices may become available that can support iBeacon capabilities such as dongles, computers, personal display assistants (PDA), and other mobile phone platforms. Dongles can be communication devices that only serve an application specific purpose and may not have a display. Exemplary receiver communication elements 204 may include but are not limited to cellular, WiFi, Bluetooth™, Near Field Communication (NFC), Zigbee, or 6LoWPAN. The communication protocol 300 between the pad 100 and the receiver 200 is Bluetooth™ 4.0 with Apple Inc.'s iBeacon protocol to alert nearby iOS devices of the communication element's 102 presence with a universally unique identifier (UUID). The protocol also allows for proximity (range) determination between the receiver 200 and communication element 102 in the pad 100.

Pad Placement with Respect to the Car Seat

As shown in FIG. 4., a preferred embodiment of an object 401 activating the pad 100, is the pad 100 disposed directly on the child car seat 400 with an object 401 sitting on the pad 100 and car seat 400. Alternatively, in FIG. 5., the pad 100 could be placed in the child car seat 400. An example of being placed within the car seat could be under the car seat fabric if accessible. Alternatively, in FIG. 6., the pad 100 can be placed on the car seat 400 headrest. Alternatively, in FIG. 7., the pad 100 could be placed in the headrest. An example of within the car seat headrest could be under the fabric of the child car seat 400. It is understood that the pad 100 could be placed on or within a conventional car seat.

Software for Receiver

The software may be written for a receiver 200 to acknowledge the presence of a powered pad 100 via iBeacon protocol. The software on the receiver 200 is stored and executed in the analysis element 203 that further stores the UUID of the pad 100 and enables the receiver 200 to automatically detect the powered pad 100 broadcasting the UUID to seamlessly identify the child in the car seat 400 without active intervention by the caregiver. The software is further able to determine the range between the pad 100 and the receiver 200. An exemplarily analysis element 203 is the memory and processor of a Bluetooth™ Low Energy compatible iOS device. The exemplary software program allows the caregiver to customize their experience with the system 1000. The exemplary software application for the receiver 200 is designed using Apple's Apple Developer Xcode. The software communication 300 between the pad 100 and receiver 200 is illustrated as three exemplarily notifications.

As shown in FIG. 8., a notification on the receiver 200 can be provided indicating that the child has been placed in a seat; interpreted by the software as a presence of the pad 100 UUID matched with the stored UUID in the analysis element 203. Future variations of iOS hardware and firmware may allow for range information to be available in the background. In a scenario where the software is running in the foreground (or future case in the background) and the last known communication 300 range was less than intermediate (few meters) between the pad 100 and receiver 200, a notification on the receiver 100 alerts the caregiver that the child was placed in the seat 400. The caregiver can make this message optional.

As shown in FIG. 9., the least level of caregiver interaction with the system 1000 is a notification on the receiver 200 indicating the child may have been left in the car seat 400; determined by the software as a loss of communication 300 between the receiver 200 and pad 100. In a scenario where the software is running in the foreground (or future case in the background) and the last known communication 300 range was far (greater than 10 meters) between the pad 100 and receiver 200, a notification on the receiver 100 alerts the caregiver they may have left the child in the car.

As shown in FIG. 10., if the software acknowledges the loss of communication between the pad 100 and receiver 200 in combination with a range less than intermediate (few meters), a positive notification is presented on the receiver 200 to confirm that the child was removed from the car can be provided to the receiver. This notification can be made optional by the caregiver. The application can further be customized with the child's name. It is understood that the notification may be a visual, haptic, or auditory. The software on the primary receiver can send notifications to other pre-determined receivers with the software. For example, the system 1000 may indicate that the child was left in a seat 400, but the driving caregiver's phone is not noticed. Another predetermined caregiver can receive a notification indicating the child is still in the seat and GPS location.

The software further allows the caregiver to interact with the receiver 200 to check the current status of the pad 100, GPS location, purchase items via e-commerce, change notification messages, and add other pads 100.

Initial Setup

The caregiver can add any additional phones to alert if the child is left in a seat, access to hardware peripherals, etc. The user will be asked to open the pad 100 to remove the protective tab to initialize the battery use. The user will then place an object on the pad 100 to active the iBeacon signal. The software on the receiver 200 will guide the caregiver through an association process to identify that UUID with their system 1000 only. Once paired, the pad 100 is placed on the car seat for use.

Use Scenario Embodiment 1 Range Available

An exemplary system 1000 use scenario is illustrated in FIG. 11. The presence state is interpreted by the software and analysis element 203 in terms of the communication 300 state and range between the receiver 200 and pad 100. The presence states described consist of: the child is placed in the car seat (communication 300 exists and range is intermediate or less), the child is sitting in the car seat (continued communication 300 exists and range is intermediate or less), and the child is left in the car seat (communication 300 ceases and last known range is far), and the child is removed from the car seat (communication 300 ceases and last known range is intermediate or less).

Pad Detected by the Receiver (Child Placed in the Car Seat)

When the child 401 is placed in the car seat 400 on the pad 100, the load 108 from the child 401 closes the switch 103 providing power 101 to the communication element 102 in the pad 100. The receiver 200 detects an iBeacon signal 300 from the pad 100 (FIG. 11. 501) whereby the software on the receiver 200 matches the stored pad 100 UUID to the pad 100 UUID stored in analysis element 203 (FIG. 11. 502). The software and analysis element 203 further determine the range between the powered pad 100 and the receiver 200 (FIG. 11. 503). The software can be configured such that, if the range between the pad 100 and the receiver 200 is intermediate or less (FIG. 11. 505), a notification (FIG. 9.) is provided on the receiver 200 (FIG. 11. 507). The caregiver can chose to disable a seating confirmation message (FIG. 9.). The software can be configured such that, if the range between the pad 100 and receiver 200 is far (FIG. 11. 504), the software will not provide a notification because the receiver is not the receiver 200 of the caregiver driving the child 401 (FIG. 11. 505). A further explanation of FIG. 11, step 505 would be two caregivers sharing the same system 1000 consisting of a pad 100 and two receivers 200. If one caregiver was driving the child out of the garage and the other caregiver remained home, this would eliminate unnecessary notifications to the caregiver remaining home as the car leaves. The software and analysis element 203 continue to poll the communication state and range between the pad 100 and receiver 100 (FIG. 11. 508). While the pad 100 and receiver 200 are in communication, the communication state is the child is near the caregiver (child is sitting in the car seat) and no further action is needed (FIG. 11. 509).

Pad No Longer Detected by the Receiver (Child Left in Car Seat after the Caregiver Leaves the Car)

While in the car, the caregiver's receiver 200 is in communication 300 with the pad 100. If the caregiver leaves the car and forgets to remove the child 401, the communication 300 will eventually cease due to the range between the receiver 200 and pad 100 exceeding a far distance (FIG. 11. 510). The software logic pairs the last known range being a far range and communication 300 loss to a child being left in the car seat (400) by the caregiver. The software provides a notification (FIG. 8) to the caregiver that the child is still in the car. In a case where only one receiver 200 is in communication 300 with the pad 100 before communication 300 ceases, and the caregiver did not acknowledge the notification by turning it off, a secondary notification is sent to another registered receiver 200 as a backup. The secondary notification can include GPS coordinates to where the car is located. An exemplary instance is the primary receiver 200 is in a state where the notification is not heard, seen or felt in a coat, handbag, etc. The secondary notification is a fail-safe that another caregiver could act upon. In a case where two receivers 200 are in communication with a pad 100 (both caregivers in the car at the same time), a child 401 is assumed to be safe as long as one receiver 200 is in communication with the pad 100. In the two-receiver 200 case, if one receiver 200 loses communication 300 with the pad 100, the software will check over the network link 204 to see if the other receiver 200 is on communication with the pad 100. If one receiver 200 is in communication 300 and the other is not, no notification is sent. If both receivers 200 lose communication 300 and the last known ranges were intermediate or less, a notification (FIG. 9) is sent to both receivers 200.

Pad No Longer Detected by the Receiver (Child Removed from Car Seat)

If the caregiver removes the child 401 from the car seat 400, the load 108 opens the switch 103 between the power 101 and the communication element 103 in the pad 100, whereby the pad 100 is powered down and no longer in communication 300 with the receiver 200 (FIG. 11. 510). The software and analysis element 203 determine the last known range between the pad 100 and receiver 200 is intermediate or less. The software logic pairs the last known range being a close range and communication 300 loss to a child being removed from the seat by the caregiver. The software provides a notification (FIG. 10.) to the caregiver. A caregiver may decide a confirmation notification may be unnecessary and disable this message in the software settings menu.

Use Scenario Embodiment 2 Range not Available

An exemplary system 1000 use scenario is illustrated in FIG. 12. The presence state is interpreted by the software and analysis element 203 in terms of the communication 300 state between the receiver 200 and pad 100. The presence states described consist of: the child is placed in the car seat (communication 300 exists), the child is sitting in the car seat (communication 300 exists), and a reminder notification sent when communication is lost between the pad and receiver (communication 300 ceases).

Pad Detected by the Receiver (Child Placed in the Car Seat)

When the child 401 is placed in the car seat 400 on the pad 100, the load 108 from the child 401 closes the switch 103 providing power 101 to the communication element 102 in the pad 100. The receiver 200 detects an iBeacon signal 300 from the pad 100 (FIG. 11. 501) whereby the software on the receiver 200 matches the stored pad 100 UUID to the pad 100 UUID stored in analysis element 203 (FIG. 12. 502). The software and analysis element 203 continue to poll the communication 300 state and range between the pad 100 and receiver 100 (FIG. 12. 508). While the pad 100 and receiver 200 are in communication, the communication 300 state is the child is near the caregiver and no further action is needed (FIG. 12. 509).

Pad No Longer Detected by the Receiver (Child Left in Car Seat after the Caregiver Leaves the Car)

While in the car, the caregiver's receiver 200 is in communication with the pad 100. If the caregiver leaves the car and forgets to remove the child 401, the communication 300 will eventually cease due to the range between the receiver 200 and pad 100 exceeding a far distance (FIG. 12. 510). After loss of communication 300, the software provides a notification to the caregiver that the child may still in the car. Because range notification information is not available, the caregiver can chose a custom message or chose from one of: FIG. 8., FIG. 9., and FIG. 10. In a case where only one receiver 200 is in communication 300 with the pad 100 before communication 300 loss, and the caregiver did not acknowledge the notification by turning it off, a secondary notification is sent to another registered receiver 200 as a backup. The secondary notification can include GPS coordinates to where the car is located. An exemplary instance is the primary receiver 200 is in a state where the notification is not heard, seen or felt in a coat, handbag, etc. The secondary notification is a fail-safe that another caregiver could act upon. In a case where two receivers 200 are in communication 300 with a pad 100 (both caregivers in the car at the same time), a child 401 is assumed to be safe as long as one receiver 200 is in communication 300 with the pad 100. In the two-receiver 200 case, if one receiver 200 loses communication 300 with the pad 100, the software will check over the network link 204 to see if the other receiver 200 is on communication with the pad 100. If one receiver 200 is in communication 300 and the other is not, no notification is sent. If both receivers 200 lose communication 300 the caregivers receive a pre-determined notification or one of: FIG. 8., FIG. 9., and FIG. 10.

Pad No Longer Detected by the Receiver (Child Removed from Car Seat)

If the caregiver removes the child 401 from the car seat 400, the load 108 opens the switch 103 between the power 101 and the communication element 103 in the pad 100, whereby the pad 100 is powered down and no longer in communication 300 with the receiver 200 (FIG. 12. 510). The software provides a notification caregivers receive a pre-determined notification (FIG. 12. 515). The pre-determined notification can be customized by the caregiver or selected by one of FIG. 8., FIG. 9., and FIG. 10.

CONCLUSION, RAMIFICATION AND SCOPE

Accordingly, the reader will see that the presence indicator for a car seat using Bluetooth™ Low Energy and the minimalistic nature of using a switch as a pseudo-sensor has advantages in that

-   -   there is no need to add additional cost in conventional sensors         to determine presence;     -   reducing the need for conventional sensors reduces power         consumption;     -   reducing processing needs of a microcontroller to handle         collection and interpretation of sensor data;     -   battery life only being used when the system is activated;     -   methods described to prevent un-wanted notifications;     -   a system that allows a caregiver to tailor interactivity and         notification to meet their daily routine while keeping their         child safe.         Although the description above contains many specifications,         these should not be construed as limiting the scope of the         invention by as merely providing illustrations of some of the         presently preferred embodiments. For example, the enclosure may         constructed of any material in any desired shape; the dimensions         of the pad are provided as exemplary only and may be of any         consumer preferred or use optimized dimension; the switch may be         toggle, pushbutton, selector, joystick, pressure, temperature,         MEMS, etc.; the Bluetooth™ element can be any that support the         iBeacon protocol; a microcontroller can be used in combination         with the Bluetooth™ radio; the application can be written in any         iOS interpretable language, etc.

Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. 

What is claimed is:
 1. A system that detects the presence of at least one object, the system comprising: a. at least one pad comprising a communication element, an identifier, a power source, a switch configured to adapt a power state from off to on by means of at least one object closing the switch disposed between the power source and the communication element; b. at least one receiver comprising an analysis element storing the unique identifier of at least one pad, a communication element in communication with at least one pad when the pad is powered on; whereby the receiver determines a presence state of at least one object when the receiver is in communication with the powered pad; and the receiver determines the presence state when the receiver loses communication with the pad.
 2. The system of claim 1 wherein the object is living.
 3. The system of claim 1 is wherein the object is inanimate.
 4. The system of claim 1 wherein the pad is further disposed on a car seat.
 5. The system of claim 1 wherein the pad is further part of a car seat.
 6. The system of claim 1 wherein the identifier is a universally unique identifier.
 7. The system of claim 1 wherein the switch is selected from the group consisting of: tactile, rocker, DIP, thumbwheel, pushbutton, toggle, slide, and cantilever.
 8. The system of claim 1 wherein the communication protocol between the pad and the receiver is Bluetooth™ 4.0 wherein the pad broadcasts the Apple Inc. iBeacon protocol in communication with the receiver.
 9. The system of claim 1 wherein the receiver is selected from the group consisting of: cell phone, computer, dongle, and personal digital assistant (PDA).
 10. A method for determining a presence state of at least one object consisting of: a. a seat containing a pad, a means by which an object closes a power switch disposed between a communication element and a power source powering the pad to broadcast a unique identifier; b. a receiver containing an analysis element storing the unique identifier of the pad, with the analysis element matching the stored unique identifier of the unique identifier broadcasted by the powered pad; c. a receiver providing a notification associated with an interpreted communication state of the receiver and the pad.
 11. The method of claim 10 wherein the interpreted communication state when the pad is in communication with the receiver is the object is in the presence of the pad.
 12. The receiver of claim 11 further generates a notification when the pad is in communication with the receiver.
 13. The method of claim 10 where the interpreted communication state when the receiver loses communication with the pad whereby the receiver generates a notification.
 14. The method of claim 10 where the notification is selected from the group consisting of: haptic, visual, light, and auditory.
 15. The method of claim 10 wherein the receiver further comprises a network link and can communicate the notification of claim 10 with at least 1 other receiver.
 16. A system that detects the presence of at least one object, the system comprising: a. at least one pad comprising a communication element, an identifier, a power source, a switch configured to adapt a power state from off to on by means of at least one object closing the switch disposed between the power source and the communication element; b. at least one receiver comprising an analysis element storing the unique identifier of at least one pad, a communication element in communication with at least one pad when the pad is powered on; whereby the receiver determines a presence state of at least one object when the receiver is in communication with the powered pad; and the receiver determines the presence state when the receiver loses communication with the pad and a last known range between the pad and the receiver.
 17. The system of claim 16 wherein the presence state of the object is in the presence of the pad when the pad is in communication with the receiver.
 18. The system of claim 16 where the presence state of the object is not in the presence of the pad when the receiver loses communication with the pad and the last known range is near whereby the receiver generates a notification.
 19. The system of claim 16 wherein the presence state of the object is not in the presence of the pad when the receiver loses communication with the pad and the last known range between the pad and the receiver is near whereby said receiver does not generate a notification.
 20. The system of claim 16 wherein the presence state of the object is in the presence of the pad when said receiver loses communication with the pad and last known range is far whereby said receiver generates a notification. 